incoming.asSequence().filter { it % 2 == 1 }.map { it*it }
?
сделал этот тест
Sequence int: 1948 ms
Sequence int: 1684 ms
Sequence int: 1686 ms
Sequence int: 1684 ms
Sequence int: 1655 ms
Sequence int: 1666 ms
Sequence int: 1663 ms
Sequence int: 1659 ms
Sequence int: 1654 ms
Sequence int: 1690 ms
Inline int: 1651 ms
Inline int: 1522 ms
Inline int: 1106 ms
Inline int: 1095 ms
Inline int: 1110 ms
Inline int: 1120 ms
Inline int: 1114 ms
Inline int: 1100 ms
Inline int: 1115 ms
Inline int: 1117 ms
Process finished with exit code 0
Inline int: 1820 ms
Inline int: 1519 ms
Inline int: 1108 ms
Inline int: 1108 ms
Inline int: 1108 ms
Inline int: 1119 ms
Inline int: 1128 ms
Inline int: 1117 ms
Inline int: 1123 ms
Inline int: 1108 ms
Sequence int: 1736 ms
Sequence int: 1698 ms
Sequence int: 1690 ms
Sequence int: 1664 ms
Sequence int: 1693 ms
Sequence int: 1713 ms
Sequence int: 1706 ms
Sequence int: 1693 ms
Sequence int: 1693 ms
Sequence int: 1688 ms
Process finished with exit code 0